Specifying the days on which automatic backup occurs

The BACKUP parameter of the DEFINE command specifies a backup cycle that specifies the days on which the host does automatic backup processing. You can also specify the day to start the cycle so that the cycle does not change with each re-initialization of DFSMShsm. In the example system, the following command is added to the ARCCMDxx member in each host:

DEFINE BACKUP(YYYYYYN CYCLESTARTDATE(1995/01/06))

The command establishes a 7-day cycle that begins on a Monday. Backup processing is done on every day except Sunday.

DFSMShsm stores the date you specify with CYCLESTARTDATE as the date the backup cycle began. If you do not specify a CYCLESTARTDATE parameter with the DEFINE command but a cycle start date is already stored and the backup cycle length has not changed, DFSMShsm uses the cycle start date that is already stored. If no cycle start date is stored and you do not specify one, DFSMShsm uses the day that the DEFINE BACKUP command is issued as the cycle start date.

If you are backing up only to DASD, you should also specify how many DASD backup volumes you want DFSMShsm to use for each day in the backup cycle.

Rule: The date specified for the cycle start date cannot be a date in the future. The date must always fall on or before the date that the DEFINE command is issued.

Specifying the days on which automatic backup occurs

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